title: IL-23 promotes maintenance but not commitment to the Th17 lineage.
abstract: IL-23 plays a critical role establishing inflammatory immunity and enhancing IL-17 production in vivo. However, an understanding of how it performs those functions has been elusive. In this report, using an IL-17-capture technique, we demonstrate that IL-23 maintains the IL-17-secreting phenotype of purified IL-17(+) cells without affecting cell expansion or survival. IL-23 maintains the Th17 phenotype over multiple rounds of in vitro stimulation most efficiently in conjunction with IL-1beta. However, in contrast to Th1 and Th2 cells, the Th17 phenotype is not stable and when long-term IL-23-stimulated Th17 cultures are exposed to Th1- or Th2-inducing cytokines, the Th17 genetic program is repressed and cells that previously secreted IL-17 assume the cytokine secreting profile of other Th subsets. Thus, while IL-23 can maintain the Th17 phenotype, it does not promote commitment to an IL-17-secreting lineage.
authors.affiliation: Department of Pediatrics, HB Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
authors.forename: Gretta L
authors.initials: GL
authors.lastname: Stritesky
authors.forename: Norman
authors.initials: N
authors.lastname: Yeh
authors.forename: Mark H
authors.initials: MH
authors.lastname: Kaplan
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000276:immunology*; D002455:Cell Division / Q000276:immunology; D019070:Cell Lineage / Q000276:immunology*; D049109:Cell Proliferation; D002470:Cell Survival / Q000276:immunology; D002478:Cells, Cultured; D016130:Immunophenotyping; D020381:Interleukin-17 / Q000096:biosynthesis* / Q000378:metabolism; D053759:Interleukin-23 / Q000378:metabolism / Q000502:physiology*; D008213:Lymphocyte Activation / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D006377:T-Lymphocytes, Helper-Inducer / Q000166:cytology / Q000276:immunology* / Q000378:metabolism*
chemical_list: D020381:Interleukin-17; D053759:Interleukin-23